The study involved 61,057 Swedish women who answered a questionnaire about their diets and then were tracked for an average of 15 years through 2004.

During that time, 301 women developed ovarian cancer. Those who reported drinking two or more cups of tea a day were 46 percent less likely to develop the disease than women who drank no tea. Drinking less than two cups also appeared to help, but not as much.

The researchers did not break out the results by tea types, but most of the tea drinkers consumed black tea. Both black and green tea contain polyphenols - substances thought to block cell damage that can lead to cancer.

Previous studies on whether tea might help prevent various kinds of cancer have yielded conflicting results. Researchers Susanna Larsson and Alicja Wolk of the Karolinska Institute in Stockholm said more research is needed to sort out the inconsistencies.

Their study was published in Monday's Archives of Internal Medicine. "If these findings are real, they'd be important because ovarian cancer is the fourth leading cause of cancer death in women," said Marji McCullough, a nutritional epidemiologist at the American Cancer Society.

Ovarian cancer is diagnosed in more than 20,000 U.S. women yearly. On average, U.S. women face about a 1-in-58 chance of developing the disease. It is hard to detect early because its symptoms, including abdominal bloating, indigestion and urinary urgency, can be vague and mimic less serious conditions.

What's not clear from this study is which type of tea is best. Sixty-eight percent of the women who took part reported drinking mainly black tea at least once a month. Previous research has suggested that green, black, and other teas all contain the antioxidants thought to be beneficial.

Green Tea Targets Cancer, New Research Finds

More Effective Than Cancer Drugs Against
Cancer-Sparking Protein Found Throughout the Body

WASHINGTON, DC – Speaking at an international conference on diet and cancer, researchers funded by the American Institute for Cancer Research (AICR) presented evidence that a major component in green tea may short-circuit the cancer process in a striking new way that scientists had not foreseen.

“We have determined that a unique quirk of biochemistry allows green tea’s protective effects to extend to many different kinds of cells,” said Dr. Thomas A. Gasiewicz, a Professor of Environmental Medicine at the University of Rochester Medical Center. “In fact, the active green tea substance – called EGCG – seems to target one protein that is particularly common throughout our bodies, and it does so with a degree of precision that cancer drugs still aren’t able to match.”

The protein in question is called HSP90, which is present at higher levels in many cancer cells. Scientists believe that in some circumstances, HSP90 helps to trigger the cascade of events that eventually leads to cancer.

When EGCG binds to this protein, however, it helps prevent these events from happening. This is important, because HSP90 is found throughout our bodies, in many different cells and tissues.

“If further research confirms that EGCG’s ability to bind to such a basic and pervasive protein enables it to extend its protective effect throughout our bodies, it explains a scientific mystery,” said Gasiewicz. “Studies that track the diets of human subjects over several years – particularly studies conducted in Asia, where green tea consumption is common – have associated regular usage of green tea with lower risk for cancers that are vastly different from one another.”

EGCG Does What Cancer Drugs Can’t Do…Yet

The protein called HSP90 is essentially a “helper” or “chaperone” protein, in that it exists to help stabilize other proteins and keep them together. Because it has to bind to so many different proteins it is present, in varying amounts, in all of our cells. In fact, it is referred to as a “promiscuous protein” because it is so pervasive.

But scientists have recently discovered that cancer cells tend to have higher levels of HSP90 than healthy cells. This has led scientists to try to develop pharmaceutical means to block HSP90, to keep it from sending the specific biochemical signals that can trigger cancer. So far, they have been unable to perfect a drug that is both highly specific and easy to administer.

What the AICR researchers have discovered is that the active substance in green tea already does what drugs still can’t do: “EGCG targets HSP90, binds directly to it, and keeps it from passing on signals that can start the cancer process,” said Gasiewicz. “As a result, potentially harmful genes are less likely to get turned on, and the cascade of events leading to cancer is cut off before it begins.”

The fact that EGCG binds directly to a protein that is found everywhere in the body suggests that it may be able to provide effective and simultaneous cancer protection in vastly different tissues and organs, Gasiewicz said.

Chamomile Tea May Help Relieve Ailments

Evidence of cold relief and easing of menstrual cramps.

January 6, 2005 -- A recent study conducted in England confirmed that drinking chamomile tea might help relieve a range of ailments including colds and menstrual cramps.

The plant used in the study was German chamomile (Matricaria ecutila), known also as manzannilla. The flowers and leaves were brewed to make a fragrant tea. Fourteen volunteers drank five cups of the tea daily for two consecutive weeks. Urine samples were tested daily before and after drinking chamomile tea.

The study found that drinking the tea was associated with a significant increase of hippurate in urine. Hippurate is a breakdown product of certain plant compounds called phenolics some of which possess antibacterial activity. This may explain why chamomile tea as an herbal medicine helps relieve colds.

It was also found in the study that drinking the tea was linked with an increase of urinary glycine, an amino acid and muscle relaxant. Glycine has been shown to relieve muscle spasms. This may explain why chamomile tea relieves menstrual cramps in women.

The study will appear in the Jan. 26, 2005 issue of Journal of Agricultural and Food Chemistry.

Buy Chamomile

Green Tea May Stall Prostate Cancer Growth

Antioxidant Found in Green Tea May Stop Prostate Cancer Spread

Dec. 1, 2004 -- Men looking for another healthy reason to drink green tea may look no further. A new study suggests that an antioxidant found in green tea may prevent prostate cancer growth by halting the spread of cancer cells and starving the tumor.

A previous study in mice suggested that polyphenols found in green tea can stop the development of prostate cancer and its growth, and researchers say this study helps explain the mechanism behind that potential health benefit.

Researchers say the green tea polyphenols appear to fight prostate cancer by targeting the mechanisms that trigger the spread of cancer cells as well as stopping the growth of neighboring blood vessels that feed the tumor.

The results of the study appear in the Dec. 1 issue of Cancer Research. The study is the latest of many that suggest that drinking green tea provides a variety of health benefits ranging from reducing heart disease risk to fighting cancer.

Explaining Green Tea's Anticancer Effects

In the study, researchers looked at the role of the antioxidants found in green tea in prostate cancer development and progression in mice. A previous study had shown that giving the mice the human equivalent of six cups of green tea per day stopped the growth of prostate cancer.

Researchers examined how the green tea antioxidant affected a protein known as insulin-like growth factor-1 (IGF-1). Increased levels of IGF-1 have been found in men with prostate cancer.

They found that mice that received the green tea antioxidant had lower levels of IGF-1 in their blood.

"These observations bear significance in light of studies that indicate increased levels of IGF-1 are associated with increased risk of several cancers, such as prostate, breast, lung and colon," says researcher Hasan Mukhtar, PhD, of the department of dermatology at the University of Wisconsin, in a news release.

Researchers say the green tea antioxidant appeared to stall cell growth by decreasing production of several proteins that promote cell survival. In addition, it reduced the production of proteins that are known to be associated with the spread of cancer cells.

Finally, the study also suggests that the antioxidant in green tea appeared to starve prostate cancer tumor cells by inhibiting the formation of blood vessels, thereby suppressing the flow of nutrients to the cancerous cells.

Tea could improve memory, study shows

Drinking regular cups of tea could help improve your memory, new research suggests.

October 27, 2004 - Results of laboratory tests by a team from the University of Newcastle upon Tyne found that green and black tea inhibit the activity of certain enzymes in the brain which are associated with memory.

The findings, which are published in the academic journal, Phytotherapy Research, may lead to the development of a new treatment for a form of dementia which affects an estimated ten million people worldwide, Alzheimer's Disease.

For their experiment, the research team, from Newcastle University's Medicinal Plant Research Centre, investigated the properties of coffee and green and black tea in a series of scientific experiments. Black tea - traditional English breakfast tea - is derived from the same plant as green tea, Camellia sinensis, but has a different taste and appearance because it is fermented.

They found that both green and black tea inhibited the activity of enzymes associated with the development of Alzheimer's Disease, but coffee had no significant effect.

Both teas inhibited the activity of the enzyme acetylcholinesterase (AChE), which breaks down the chemical messenger or neurotransmitter, acetylcholine. Alzheimer's is characterised by a drop in acetylcholine.

Green tea and black tea also hinder the activity of the enzyme butyrylcholinesterase (BuChE), which has been discovered in protein deposits which are found on the brain of patients with Alzheimer's.

Green tea went one step further in that it obstructed the activity of beta-secretase, which plays a role in the production of protein deposits in the brain which are associated with Alzheimer's disease. Scientists also found that it continued to have its inhibitive effect for a week, whereas black tea's enzyme-inhibiting properties lasted for only one day.

There is no cure for Alzheimer's but it is possible to slow the development of the disease. Drugs currently on the market hinder the activity of AChE, and others are being developed which scientists hope will inhibit the activity of BuChE and beta-secretase.

However, many of the drugs currently available, such as donepezil, have unpleasant side effects and the medical profession is keen to find alternatives.

The Newcastle University researchers are now seeking funding to carry out further tests on green tea, which they hope will include clinical trials. Their aim is to work towards the development of a medicinal tea which is specifically aimed at Alzheimer's sufferers.

The next step is to find out exactly which components of green tea inhibit the activity of the enzymes AChE, BuChE and beta-secretase.

Lead researcher, Dr Ed Okello, who is also a lecturer with Newcastle University's School of Biology, said: "Although there is no cure for Alzheimer's, tea could potentially be another weapon in the armoury which is used to treat this disease and slow down its development. It would be wonderful if our work could help improve the quality of life for millions of sufferers and their carers.

"Our findings are particularly exciting as tea is already a very popular drink, it is inexpensive, and there do not seem to be any adverse side effects when it is consumed. Still, we expect it will be several years until we are able to produce anything marketable.

Dr Okello, himself a green tea drinker, said the findings of the research suggested tea could boost the memory of everyday drinkers: "The ageing politician, Tony Benn, is a prime example of somebody who drinks tea and has a fantastic memory. He is said to drink 18 pints a day and has a very sharp mind for a man of his age," he added.

Prof Clive Ballard, director of research, Alzheimer's Society, said: "This interesting research builds on previous evidence that suggests that green tea may be beneficial due to anti-oxidant properties. Certainly the effect on the cholinesterase enzyme (the target of current anti-dementia drugs such as Aricept) and beta-secretase (an enzyme which is important in the build up of plaques) is very exciting and requires further investigation."
 

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